Collapsible longeron structures

ABSTRACT

Embodiments of the invention are directed toward rollable and collapsible structures. These structures, for example, can include a plurality of tubular longerons with a slit or gap that extends along the longitudinal length of the longerons. Such longerons can be combined in an arrangement that creates a structure. The structure can be collapsed and the longerons rolled either singularly or as a group into a stowed configuration.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/036,199, filed Feb. 28, 2011, entitled “DeployableStructures Having Collapsible Structural Members”, and U.S. patentapplication Ser. No. 13/014,299 filed Jan. 26, 2011, entitled“Collapsible Structures With Adjustable Forms”, the disclosures of whichare incorporated by reference in their entirety herein for all purposes.

BACKGROUND

Portable structures that can be deployed and stowed come in a number ofconfigurations and can be used in a number of ways. Tents, for example,can be stowed in a compact form and set up or deployed for a variety ofuses.

BRIEF SUMMARY

Embodiments of the invention include tubular longerons that can have adeployed and a stowed state. In the stowed state one or more tubularlongerons can be rolled into a single roll. In the deployed state, oneor more tubular longerons can be extended and formed into a structure.This longeron structure, for example, can be an A-frame-shapedstructure. Embodiments of the invention can provide large, usablestructures that can be combined and/or stowed in a small stowedconfiguration.

The terms “invention,” “the invention,” “this invention” and “thepresent invention” used in this patent are intended to refer broadly toall of the subject matter of this patent and the patent claims below.Statements containing these terms should not be understood to limit thesubject matter described herein or to limit the meaning or scope of thepatent claims below. Embodiments of the invention covered by this patentare defined by the claims below, not this summary. This summary is ahigh-level overview of various aspects of the invention and introducessome of the concepts that are further described in the DetailedDescription section below. This summary is not intended to identify keyor essential features of the claimed subject matter, nor is it intendedto be used in isolation to determine the scope of the claimed subjectmatter. The subject matter should be understood by reference to theentire specification of this patent, all drawings and each claim.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrative embodiments of the present invention are described indetail below with reference to the following drawing figures:

FIG. 1A shows a longeron structure in an unrolled configurationaccording to some embodiments of the invention.

FIG. 1B shows a longeron structure in a deployed configuration accordingto some embodiments of the invention.

FIG. 2A shows a longeron structure in an unrolled configurationaccording to some embodiments of the invention.

FIG. 2B shows a longeron structure in a deployed configuration accordingto some embodiments of the invention.

FIG. 3A shows another longeron structure in an unrolled configurationaccording to some embodiments of the invention.

FIG. 3B shows the longeron structure in FIG. 3A in a foldedconfiguration according to some embodiments of the invention.

FIG. 3C shows the longeron structure in FIG. 3A used in a longeronstructure according to some embodiments of the invention.

FIG. 3D shows a longeron structure according to some embodiments of theinvention.

FIG. 4 shows a tubular longeron being rolled from a deployed to a stowedconfiguration according to some embodiments of the invention.

FIG. 5A shows a tripod constructed from three longerons according tosome embodiments of the invention.

FIG. 5B shows a tripod coupled with a sheet of solar arrays.

FIG. 5C shows three longerons aligned along their longitudinal lengthand in the process of being rolled into a stowed configuration.

FIGS. 6A, 6B, and 6C show various views of a complex longeron andaccording to some embodiments of the invention.

FIG. 6D shows a longeron structure formed with complex longeronaccording to some embodiments of the invention.

FIG. 7 shows a longeron structure with a curved cross-member longeronaccording to some embodiments of the invention.

FIG. 8 shows a structure with two additional interior legs according tosome embodiments of the invention.

FIGS. 9A and 9B are examples of longerons with complex shapes accordingto some embodiments of the invention.

FIGS. 10A and 10B show a longeron structure with six supporting legsaccording to some embodiments of the invention.

FIG. 11 shows a longeron structure coupled with a solar array panelaccording to some embodiments of the invention.

FIG. 12 shows a picture frame longeron structure according to someembodiments of the invention.

FIG. 13 shows a longeron structure with a strap coupled with a bagaccording to some embodiments of the invention.

DETAILED DESCRIPTION

The subject matter of embodiments of the present invention is describedhere with specificity to meet statutory requirements, but thisdescription is not necessarily intended to limit the scope of theclaims. The claimed subject matter may be embodied in other ways, mayinclude different elements or steps, and may be used in conjunction withother existing or future technologies. This description should not beinterpreted as implying any particular order or arrangement among orbetween various steps or elements except when the order of individualsteps or arrangement of elements is explicitly described.

Embodiments of the invention employ various longerons to create longeronstructures. These longerons can have a number of configurations. Forexample, the longerons disclosed herein can be constructed such thatthey may be flattened and rolled for stowage. The longerons can regaintheir original cross-section during deployment. The disclosed longeronstypically include a long tube with one or more slits or gaps that extendthrough the longitudinal length of the longeron. The slits may allow thetube to be flattened and rolled. When rolled, the longerons can bestacked or combined and collectively rolled together. The longerons maybe constructed from any type of composite material that may, forexample, include metal, graphite, or polymer.

Embodiments of the invention include deployable and stowable longeronstructures constructed from these longerons. When deployed, theselongeron structures can be standalone longeron structures and/or can beused as a tent and/or a longeron structure that is coupled with solararrays. A plurality or all of these longerons can be embedded withineach other and rolled up into a single stowed configuration. In someembodiments, each longeron can be rolled into separate stowedconfigurations.

For added flexural properties the longerons may have some curvature muchlike a carpenter's tape. Longerons may also be stiffened by anothermechanism such as a sandwich panel that can be collapsed for stowage.

FIG. 1A shows longeron 100 according to some embodiments of theinvention. Longeron 100 is a tubular member having first end 110 andsecond end 140 with gap 120 (or slit) extending along the longitudinallength of the longeron from first end 110 to second end 140. With thisslit (or gap) longeron 100 can be referred to as a slit-tube longeron.Generally speaking, longerons described here include a slit or gapunless otherwise specified. Longeron 100 also includes partial slit 112at first end 110 and partial slit 142 at second end 140. Partial slit112 separates a portion of longeron 100 at first end 110 into first leg114 and second leg 116. Partial slit 142 separates a portion of longeron100 at second end 140 into third leg 144 and fourth leg 146. In someembodiments, longeron 100 can include reinforced material where partialslits 112 and 142 end.

Longeron 100 can include three states: a rolled state, a deployed state,and a resting state. FIG. 1A shows longeron 100 in the resting state. Inthis state, the longeron is unrolled and unrolled (undeployed). In therolled state, longeron 100 is flattened and rolled along thelongitudinal length of longeron 100 (see FIG. 4, for example).

FIG. 1B shows longeron 100 in the deployed state. In this state, legs114 and 116 are separated along partial slit 112 and bent (e.g., split,hinged, folded, etc.) to form structural legs. Similarly, legs 144 and146 are separated along partial slit 142 and bent to form structurallegs. Sheer members 122 can be used to keep legs 114, 116, 144, or 146from returning to the relaxed configuration. These sheer members can becoupled with legs 114, 116, 144, 146 and/or cross member 132. Sheermember 122 can be any type of strap and/or tether comprising, forexample, fabric, leather, or composite material. Sheer member 122 mayalso be compliant to allow rolling and/or unrolling with longerons. Theportion of longeron 100 where legs 114, 116, 144, or 146 bend longeron100 may be reinforced or be more compliant to accommodate such bending.Cross member 132 may or may not be a slit-tube longeron.

FIG. 2A shows another longeron combination that has rolled, unrolled,and/or deployed states. FIG. 2A shows main longeron 200 according tosome embodiments of the invention coupled with first longeron 212 andsecond longeron 214. First longeron 212 and/or second longeron 214 canbe coupled with main longeron 200, for example, with a rivet atattachment point 215. First longeron 212 and second longeron 214 can befolded so they extend in the same direction away from attachment points215. Various other mechanisms may be used to attach the longerons. Thelongerons can be attached in such a way that first longeron 212 andsecond longeron 214 can rotate about the attachment point. Moreover,first longeron 212 can be attached with main longeron 200 such thatfirst longeron 212 is substantially aligned with first end 222 of mainlongeron 200 and second longeron 214 can be attached with main longeron200 such that second longeron 214 is substantially aligned with secondend 224 of main longeron 200. Various techniques can be used to forcelongeron 214 and longeron 212 to fold in the proper direction.

Main longeron 200 can include three states: a rolled state, a deployedstate, and a resting state. FIG. 2A shows main longeron 200 in theresting state. In this state, the longeron is unrolled and undeployed.In the rolled state, main longeron 200 along with first longeron 212 andsecond longeron 214 is flattened and rolled along the longitudinallength of main longeron 200 (see FIG. 4, for example).

FIG. 2B shows main longeron 200 in the deployed configuration. In thisconfiguration, first longeron 212 and second longeron 214 are rotatedand extended as legs along with first end 222 and second end 224. Sheermembers 122 can be used to keep first end 222, second end 224, firstlongeron 212, and second longeron 214 from returning to the relaxedconfiguration. The portion of main longeron 200, where first end 222and/or second end 224 bend, may be reinforced with additional ordifferent material (e.g., composite material or adhesive) to accommodatesuch bending. Similarly, first longeron 212 and second longeron 214 canbe reinforced along portions where they bend. Sheer members 122 can becoupled with longerons 212, 214, 222, 224 and/or cross member 132. Crossmember 132 may or may not be a slit-tube longeron. In some embodiments,longerons may have portions that are more compliant to accommodatebending. Such portions can have different or less material (e.g.,composite material or adhesive) to accommodate such bending.

First longeron 212 and second longeron 214 can be rotated around 215 ineither direction along the length of longeron 200 either toward theinterior of longeron 200 or away from the interior of longeron 200.

FIG. 3A shows reverse longeron 300 that includes two longerons 310 and320 conjoined at 330 according to some embodiments of the invention. Thetwo longerons have gaps 311 and 321 on opposite sides of theirlongitudinal lengths. Reverse longeron 300 flattens out at the portionof the longeron where longerons 310 and 320 are conjoined 330. Longerons310 and 320 can be conjoined using any technique known in the art. Insome embodiments, longerons 310 and 320 can be constructed fromcomposite materials and/or can be conjoined using glues or chemicalssimilar to those in construction of the composite materials. In someembodiments, conjoined portion 330 of reversed longeron 300 can bereinforced to allow for bending without causing damage to reverselongeron 300.

FIG. 3B shows reverse longeron 300 in a folded configuration. Becauselongerons 310 and 320 have openings on opposite sides of theirlongitudinal lengths, reverse longeron 300 can fold upon itself atconjoined portion 330. After being folded, reverse longeron 300 can berolled along the longitudinal length of the folded reverse longeron intoa stowed configuration.

FIG. 3C shows A-frame longeron structure 350 constructed with tworeverse longerons according to some embodiments of the invention.A-frame longeron structure 350 includes two reverse longerons 300coupled with cross member 360, which can also be a tubular longeron witha slit along its longitudinal length. Reverse longerons 300 are foldedover at conjoined portion 330. Reverse longerons 300 can be coupled withcross member 360 using any number of coupling techniques includingVelcro, snaps, buttons, etc. And, in some embodiments, reverse longerons300 can be coupled with cross member 360 with sheer members 122.

FIG. 3D shows A-frame longeron structure 380, similar to longerstructure 350, but constructed with two non-reverse longerons accordingto some embodiments of the invention. A-frame longeron structure 380includes two longerons 385 coupled with cross member 360, which can alsobe a tubular longeron with a slit along its longitudinal length. Whendeployed as shown in the figure, longerons 385 are flattened in middleportion 390 and folded as shown. Longerons 380 can be coupled with crossmember 360 using any number of coupling techniques including Velcro,snaps, buttons, etc. And, in some embodiments, longerons 380 can becoupled with cross member 360 with sheer members 122.

FIG. 4 shows tubular longeron 400 being rolled from into a stowedconfiguration. When rolling such a longeron, the tubular walls oflongeron 400 can be opened and/or flattened. Then longeron 400 can thenbe rolled into a stowed configuration. Often portions of the longeronare progressively flattened as the longeron is rolled up. As describedpreviously, multiple longerons can be stacked upon one another orembedded within each other in the tubular or deployed state. Thecombined longeron stack can then be rolled along the longitudinal lengthof the longeron into the stowed configuration. In some embodiments, themany tubular longerons that form any of the longeron structures shown inFIGS. 1B, 2B and 3C can be collapsed and rolled into a single stowedroll.

In some embodiments of the invention longeron structures can includemultiple longerons like those shown in FIGS. 1A, 1B, 2A, 2B, 3A, 3B and3C. In some embodiments the various longerons can be rolled together ina single roll, or in multiple rolls. Some rolls may include individuallongerons and others may include or two or more longerons rolledtogether. During deployment the longerons can be unrolled and coupledtogether, for example, using snaps, pins, hook-and-loop fastener,straps, buckles, etc. Once the longeron structure is deployed orconstructed a sheet of solar arrays can be coupled with the structure.During deployment the sheet of solar arrays can be decoupled, thelongeron structure taken down by removing the various attachmentmechanisms, and the various longerons rolled up either individuallyand/or collectively.

FIG. 5A show tripod 500 constructed from three longerons 505, 510, and515 according to some embodiments of the invention. The three longerons505, 510, and 515 comprise the three legs of tripod 500. Longerons 505,510, and 515 are coupled together at one end of each longeron to formthe tripod longeron structure. FIG. 5B shows tripod 500 with a sheet ofsolar arrays 520. Various other longeron structures can be coupled withtripod 500. Indeed, tripod 500 can be used in any collapsible and/ormobile longeron structure.

FIG. 5C shows the three longerons aligned along their longitudinallength. The longerons are nested in their deployed configuration 550 androlled along their longitudinal length. Element 550 show the threelongerons nested in their elongated shape. Element 550 shows thelongerons flattened and element 560 shows a partially rolled portion ofthe longerons. In this way, the three longerons are flattened and rolledtogether. The longerons can be unrolled together as well. The attachmentpoint, where all three longerons are coupled together is configured toallow the longerons to be aligned and/or nested for rolling and stowage.In some embodiments, the longerons can be detachably coupled together.In such embodiments, the three longerons can be nested and rolledtogether or rolled individually.

FIG. 6A shows a top view of complex longeron 600, FIG. 6B shows thefront side of complex longeron 600 and FIG. 6C shows the back side ofcomplex longeron 600. Complex longeron 600 comprises a plurality oflongerons coupled together according to some embodiments of theinvention. Complex longeron 600 can include cross member longeron 610and two separate longerons on each end. Cross member longeron 610 canhave a diameter that is larger than the diameter of other portions ofcomplex longeron 600. Cross member longeron 610 can have a diameter thatis 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0, etc. times larger thanthe diameter of other portions of complex longeron 600. Cross memberlongeron 610 can include slit 605 that extends along its longitudinallength. Slit 605 can have any width or thickness.

On both longitudinal ends cross member longeron 610 is coupled with twoseparates leg longerons: leg longeron 620 and leg longeron 622 on oneend as well as leg longeron 624 and leg longeron 626 on the other end.Each leg longeron comprises a slit-tube longeron with a diameter smallerthan the diameter of cross member longeron 610 and a slit or gap alongthe longitudinal length of the leg longeron. In some embodiments slit605 can correspond with gap 606 that separates the two legs on each end.

In some embodiments, cross member longeron 610 can have portions thathave diameters that reduce from the larger diameter of cross memberlongeron 610 to a smaller diameter. In other embodiments, the leglongerons can have portions that have diameters that increase from thesmaller diameter of the leg longeron to a larger diameter to couple withcross member longeron 610.

While complex longeron 600 includes five longerons: cross member 610 andleg longerons 620, 622, 624, and 626; any number of longerons can beused. These longerons can be coupled together using any number oftechniques. For example, the longerons can comprise composite materialsand can be coupled together using any composite binding techniques knownin the art. As another example, the longerons can be fabricated togetheras a single unitary longeron structure using composite fabricationtechniques.

Complex longeron 600 can be flattened and rolled into a stowedconfiguration; each individual longeron can be flattened and rolledtogether as a group into a single stowed roll.

FIG. 6D shows a longeron structure formed with complex longeron 600according to some embodiments of the invention. Leg longerons 620 and622 can be extended and separated at one end and leg longerons 624 and626 can be extended and separated at the other end. These leg longeronscan support cross member longeron 610. Various straps, connectors,clips, etc. can be used to aide in holding this configuration. Thelarger diameter of cross member longeron 610 can allow it to supportgreat loads.

FIG. 7 shows longeron structure 700 with curved cross-member longeron710 according to some embodiments of the invention. Curved cross-memberlongeron 710 can support greater loads than a straight cross-memberand/or can decrease the forces at the joint of legs 720, 722, 724, 726and cross-member longeron 710. Curved cross-member longeron 710 can beused with any embodiment of the invention. For example, curvedcross-member longeron 710 can have a wider the same, a smaller, or awider diameter cross member than other portions of the longeronstructure. As another example, curved cross-member longeron can becoupled with legs of various sizes and/or configurations.

FIG. 8 shows longeron structure 800 with two additional interior legs823, 825 according to some embodiments of the invention. Interior legs823 and 825 can be coupled with the other longerons making up longeronstructure 800 in any way. For example, interior legs 823 and 825 can bepart of a single longeron as shown in FIG. 1A, but with two partialslits that form three longeron shaped legs, one of which can be eitheror both of legs 823 and 825. As another example, interior legs 823 and825 can comprise fifth and sixth legs respectively as shown in FIG. 2A.Legs 823 and 825 can be coupled with longeron structure as describedabove. As another example, longeron structure 800 can have a curvedcross-member as shown in FIG. 7 and/or a cross-member with a largerdiameter as shown in FIG. 8.

In some embodiments of the invention, longerons can have complex shapes.For example, longerons can have cross-sectional shapes that vary alongthe length of the longeron. As another example, longerons can havethicknesses that vary along the length of the longeron. FIGS. 9A and 9Bare examples of longerons with complex shapes. FIG. 9A shows longeron900 with middle section 910 that has a wider cross section than otherportions of longeron 900. FIG. 9B shows longeron 950 that has a smallercross section than other portions of longeron 960. Various combinationsof wider and/or smaller cross sections can be extended along thelongitudinal length of a longeron.

Longeron structures can have any number of cross members and/or legs andcan come in a variety of configurations. One example of such a longeronstructure is shown in FIGS. 10A and 10B. FIG. 10A shows longeronstructure 1000 unrolled. And FIG. 10B shows longeron structure 1000completely deployed. Longeron structure 1000 includes cross memberlongeron 1005 and/or six legs 1010, 1012, 1014, 1016, 1018, and 1020.Each longeron may comprise a tubular structure with slit 1006 along thelongitudinal length of the longeron. Longeron structure 1000 is similarto longeron structure 200 shown in FIGS. 2A and 2B with the addition ofinterior legs 1014 and 1016 that can be secured on the interior (insideslit 1006) or exterior of cross member longeron 1005.

FIG. 11 shows longeron structure 1105 coupled with solar array panel1110 according to some embodiments of the invention. Longeron structure1105 can be any longeron structure shown in any of the figures and ourdescribed in throughout this specification. Solar array panel 1110 canbe a sheer member that provides structural strength to longeronstructure 1105. The sheer forces in solar array panel 1110 can keep thelegs of longeron structure stable.

FIG. 12 shows picture frame longeron structure 1200 according to someembodiments of the invention. Longeron structure 1200 can includelongeron 1210 that can be formed into a picture frame shape as shown inthe figure. That is, longeron 1210 can be form the perimeter of apolygon (e.g., a rectangle) by bending in certain positions of thelongeron. A single longeron can be wrapped and the two ends coupledtogether with any type of attachment mechanism. Or two or more longeronscan have their ends coupled together to form the picture frame. Pictureframe longeron structure 1200 can include kick stand longerons 1205coupled with longeron 1210 to prop up picture frame longeron structure1200 at an angle. The kick stand longerons can be adjusted to change theangle of the picture frame relative to the sky.

In some embodiments, the various longerons making up a collapsiblestructure may have different diameters and/or lengths. Moreover, thevarious longerons can have variable diameters, thickness, etc. Theselongerons may also be comprised of different material. Moreover, stakesand/or tethers can be sued to secure the structures to the ground.

In some embodiments longeron structures can include feet positioned atthe end of any of the longeron structures. These feet can be longeronsor other material. In some embodiments the longeron structures caninclude a grommet that can be used in conjunction with a stake to securethe longeron structure to the ground. The grommet can be disposed withthe feet, be part of a strap, or be included in the longeron.

FIG. 13 shows longeron structure 1300 with strap 1305 coupled with bag1310 according to some embodiments of the invention. Bag 1310 caninclude a net, pouch, bag, pocket, bucket, etc. that can be filled withweighted material and can be used to hold longeron structure 1300 inplace during use. For instance, a user can fill the net with rocks orother material. The length of strap 1305 can be long enough so that bag1310 rests on the ground or floats above the ground.

Different arrangements of the components depicted in the drawings ordescribed above, as well as components and steps not shown or describedare possible. Similarly, some features and subcombinations are usefuland may be employed without reference to other features andsubcombinations. Embodiments of the invention have been described forillustrative and not restrictive purposes, and alternative embodimentswill become apparent to readers of this patent. Accordingly, the presentinvention is not limited to the embodiments described above or depictedin the drawings, and various embodiments and modifications can be madewithout departing from the scope of the claims below.

What is claimed is:
 1. A longeron structure comprising: a tubularlongeron having a first end, a second end, and a longitudinal lengthextending from the first end to the second end, wherein the tubularlongeron includes a gap extending along the longitudinal length of thetubular longeron from the first end to the second end, a first slit atthe first end extending a long a portion of the longitudinal length ofthe tubular longeron, and a second slit at the second end extending along a portion of the longitudinal length of the tubular longeron. 2.The longeron structure according to claim 1, wherein the longeronstructure comprises a rolled configuration wherein the tubular longeronis rolled along the longitudinal length of the tubular longeron.
 3. Thelongeron structure according to claim 1, wherein the longeron structurecomprises a deployed configuration wherein the tubular longeron is bentat the first slit.
 4. The longeron structure according to claim 3,wherein the longeron forms two legs when the tubular longeron is splitat the first slit.
 5. The longeron structure according to claim 1,wherein the longeron structure comprises a deployed configurationwherein the tubular longeron is split at the second slit.
 6. Thelongeron structure according to claim 5, wherein the tubular longeronforms two legs when the longeron is split at the second slit.
 7. Thelongeron structure according to claim 1, wherein the tubular longeron iscurved along the longitudinal length of the longeron.
 8. The longeronstructure according to claim 1, wherein the tubular longeron comprises across section that varies along the longitudinal length of the tubularlongeron.
 9. A longeron structure comprising: a main tubular longeronhaving a first end, a second end, a longitudinal length extending fromthe first end to the second end, and a gap along the longitudinal lengthof the longeron from the first end to the second end; and a firsttubular longeron having a first end, a second end, a longitudinal lengthextending from the first end to the second end, and a gap extendingalong the longitudinal length of the longeron from the first end to thesecond end, wherein the longitudinal length of the first tubularlongeron is shorter than the longitudinal length of the main tubularlongeron, and wherein the second end of the first tubular longeron iscoupled with the main tubular longeron at a first couple point such thatthe first tubular longeron can rotate about the couple point.
 10. Thelongeron structure according to claim 9, wherein the longeron structurecomprises a rolled configuration wherein the main tubular longeron andthe first tubular longeron are rolled along the longitudinal length ofthe longerons.
 11. The longeron structure according to claim 9, whereinthe longeron structure comprises a deployed configuration wherein thefirst tubular longeron and a portion of the main tubular longeron formtwo legs.
 12. The longeron structure according to claim 9, wherein thelongitudinal length of the first tubular longeron is less than half thelongitudinal length of the main tubular longeron.
 13. The longeronstructure according to claim 9, further comprising a shear membercoupling the first tubular longeron with the main tubular longeron. 14.The longeron structure according to claim 13, wherein the shear membercomprises a strap or a photovoltaic sheet.
 15. The longeron structureaccording to claim 9, further comprising: a second tubular longeronhaving a first end, a second end, a longitudinal length extending fromthe first end to the second end, and a gap extending along thelongitudinal length of the longeron from the first end to the secondend, wherein the longitudinal length of the second tubular longeron isshorter than the longitudinal length of the main tubular longeron, andwherein the second end of the first tubular longeron is coupled with themain tubular longeron at a second couple point such that the firsttubular longeron can rotate about the couple point.
 16. The longeronstructure according to claim 15, wherein the longeron structurecomprises a rolled configuration wherein the main tubular longeron, thefirst tubular longeron, and the second tubular longeron are rolled alongthe longitudinal length of the longerons.
 17. The longeron structureaccording to claim 15, wherein the longeron structure comprises adeployed configuration wherein the second tubular longeron and a portionof the main tubular longeron form two legs.
 18. The longeron structureaccording to claim 15, further comprising a strap coupling the secondtubular longeron with the main tubular longeron.
 19. A longeronstructure comprising: a first longeron having a first end, a second end,a longitudinal length extending from the first end to the second end,and a gap extending along the longitudinal length of the longeron fromthe first end to the second end, wherein the first longeron includes afirst attachment mechanism near the first end and a second attachmentmechanism near the second end; a second longeron having a first end, asecond end, a longitudinal length extending from the first end to thesecond end, and a gap extending along the longitudinal length of thelongeron from the first end to the second end, wherein the secondlongeron includes a third attachment mechanism positioned between thefirst end and the second end of the second longeron and configured tocouple with first attachment mechanism; and a third longeron having afirst end, a second end, a longitudinal length extending from the firstend to the second end, and a gap extending along the longitudinal lengthof the longeron from the first end to the second end, wherein the thirdlongeron includes a fourth attachment mechanism positioned between thefirst end and the second end of the third longeron and configured tocouple with second attachment mechanism.
 20. The longeron structureaccording to claim 19, wherein the first, second, third and fourthattachment mechanisms comprise a snap, Velcro, carabineers, etc.
 21. Thelongeron structure according to claim 19, further comprising a shearmember coupling at least two of the first longeron, the second longeron,and the third longeron.